The synthesis of the glycidyl carbamate functional group by the reaction of an isocyanate functional compound and glycidol is known to those skilled in the art.
Farissey and Nashu (Journal of Heterocyclic Chemistry, 1970, 7, 331-333) disclose the synthesis of a glycidyl carbamate model compound and the intramolecular rearrangement reaction at elevated temperatures to a hydroxyoxazoline.
U.S. Pat. No. 4,397,993 discloses oxirane-containing polyurethane polymers where the oxirane is part of a glycidyl carbamate group. Crosslinking of the polymer is effected by reaction of the polymer with an epoxy crosslinking agent which can be a polyol or polyamine. This patent also discloses a “self-crosslinkable” polymer, however the self-crosslinkable polymer incorporates unreacted isocyanate groups.
U.S. Pat. No. 4,950,722 discloses the synthesis of an unsaturated epoxy that contains carbamate functionality. Mixtures of this compound with conventional epoxy resins as well as the vinyl copolymerization with other unsaturated monomers was described.
Chen et al. (J. Applied Polymer Science, 51, 1199 (1994); J. Applied Polymer Science, 52, 1137 (1994)) discloses the preparation of glycidyl-terminated polyurethane resins. Polyamines were used to crosslink the polymers. Blends of the glycidyl-terminated polyurethane resins with conventional epoxy resins were also prepared and crosslinked with polyamines.
Edwards, et al. (Polymer Preprints, 44(1), 144 (2003); Polymer Preprints, 44(1), 54 (2003); Polymeric Materials: Science and Engineering, 90, 455 (2004); Prog. Org. Coat., 57, 128-139 (2006)) discloses the synthesis of multifunctional glycidyl carbamate functional oligomers from polyfunctional isocyanates and glycidol. The self-crosslinking reaction to form coatings with good performance was also described.
Edwards, et al. (Polymer Preprints, 45(1), 935 (2004); JCT Research 2(7), 517-528 (2005)) described the crosslinking of the multifunctional glycidyl carbamate functional oligomers with polyfunctional amines to form hard and flexible coatings having good solvent resistance.
The glycidyl carbamate resins described by Edwards, et al. are the reaction products of multifunctional isocyanates with glycidol. Two such resins are illustrated below and are based on the hexamethylene diisocyanate triisocyanurate trimer (IGC) and biuret trimer (BGC), respectively.

These resins can be self-crosslinked or crosslinked with amines to produce coatings. However, the resins have very high viscosity and a large amount of solvent is needed to make coatings, especially coatings that can be applied using spray, brush, or roller application methods.
Thus, what is needed in the art is a way of reducing the viscosity while maintaining the reactivity and good properties of these glycidyl carbamate functional resins. This invention answers that need.